import { NgxQrcodeStylingModule } from 'ngx-qrcode-styling';

@NgModule({
    imports: [
        NgxQrcodeStylingModule
    ]
})

import { Options } from 'ngx-qrcode-styling';

export class AppComponent {
  public config: Options = {
    width: 300,
    height: 300,
    data: "https://www.facebook.com/",
    image: "https://upload.wikimedia.org/wikipedia/commons/5/51/Facebook_f_logo_%282019%29.svg",
    margin: 5,
    dotsOptions: {
      color: "#1977f3",
      type: "dots"
    },
    backgroundOptions: {
      color: "#ffffff",
    },
    imageOptions: {
      crossOrigin: "anonymous",
      margin: 0
    }
  };
}

import { NgxQrcodeStylingComponent, Options } from 'ngx-qrcode-styling';

export class AppComponent {
    @ViewChild('qrcode', { static: false }) public qrcode!: NgxQrcodeStylingComponent;

    onUpdate(): void {
        this.qrcode.update(this.qrcode.config, {
          // height: 300,
          // width: 300,
          frameOptions: {
            height: 600,
            width: 600,
          },
          ...
        }).subscribe((res) => {
          // TO DO something!
        });
    }
    
    onDownload(): void {
        this.qrcode.download("file-name.png").subscribe((res) => {
          // TO DO something!
        });
    }
}

import { NgxQrcodeStylingService, Options } from 'ngx-qrcode-styling';

export class AppComponent implements AfterViewInit {
    @ViewChild("canvas", { static: false }) canvas: ElementRef;
    public config: Options = {...};
    
    constructor(private qrcode: NgxQrcodeStylingService) {}

    ngAfterViewInit(): void {
        // Create QRCode by Service and ElementRef 
        this.qrcode.create(this.config, this.canvas.nativeElement).subscribe((res) => {
          // TO DO something!
        });
    }
}

import { NgxQrcodeStylingService, Options } from 'ngx-qrcode-styling';

export class AppComponent implements AfterViewInit {
    public config: Options = {...};
    
    constructor(private qrcode: NgxQrcodeStylingService) {}
   
    ngAfterViewInit(): void {
        // Create QRCode by Service and HTMLElement 
        this.qrcode.create(this.config, document.getElementById('canvas')).subscribe((res) => {
          // TO DO something!
        });
    }
}